In Windows an X-Window server needs to installed to allow UNIX/Linux to display GUIs. The smallest free functional X-Window server that I found is called Xming and can be downloaded from here.

After Xming is installed (run the setup.exe), it needs to be started before a putty session is opened to the UNIX/Linux server (In our case, jaguar).
When you have started it, you should see it in your task bar

After that, users need to run putty and do the following before opening an SSH session:

1. From the left panel in putty, users should expand the SSH branch and point to X11 choice.
2. After pointing to X11, the "Enable X11 forwarding" check box has to be checked!!

OK, now choose Session in the Category Window so you get the option to open a PuTTYsession where you want:

Now users can open the SSH session where putty will automatically set the DISPLAY environment variable; in the opened SSH session, users can see GUIs in their windows machine rendered by the Xming.

Thanks Maitham!

OK, Here I am not so sure...I do know that the following works from one UNIX machine to another - I have never tested it for a Linux box or Mac.

If this does not work and anyone has a techique for Macs and/or Linux that does, please send me (amk@ecst.csuchico.edu) an email and I will put it here too.

To set your $DISPLAY variable on the UNIX server to "forward" your GUIs to your local IP_address, once on the host machine change your DISPLAY variable:
Korn Shell: export DISPLAY=ip_address:0
C Shell: setenv DISPLAY=ip_address:0

Where obviously the ip_address is the IP_address of the machine you are working on.

I also found this but have not tried either.